The present invention relates to a system and method which employ a handheld computer to collect, display and upload engine/vehicle data to a personal computer for analysis.
The advantages and benefits associated with extracting, displaying and analyzing data from engine powered equipment, such as vehicles, is well recognized and accepted. Fleet operators can examine the accrued data to determine service needs and improper equipment utilization. Service personnel can use the collected information to identify the cause of any failure, to aid in diagnosis, to predict future failures, to schedule maintenance/repairs, and to correct any problems before an actual failure occurs. Such diagnosis and failure prediction are particularly pertinent to automobiles, trucks and static installations of engine powered equipment, such as diesel powered electrical generators, so that minor problems can be repaired before they lead to catastrophic failures and so that servicing can be scheduled during periods in which equipment will be least affected. Elaborate systems for collecting and intelligently analyzing the data have been developed as disclosed, for example, in U.S. Pat. No. 5,737,215 to Schricker et al..
Modern electronically controlled vehicles and engines, such as diesel truck engines, are typically equipped with a variety of electronic equipment including for example sensors, electronic fuel control systems, and on-board computer control modules all of which is interconnected by a shared communication path called a data link. Attempts have been made to standardize the protocol used by such data links. For example, the Society of Automotive Engineers (SAE) has adopted data link standards, such as J1708 and more recently J1939, that provide for serial data communication between microcomputer systems in heavy duty vehicle applications. SAE has also adopted a J1587 standard for electronic data interchange between microcomputer systems and heavy duty vehicle applications that specifies the format of data and messages communicated among microprocessors connected to a shared data link. U.S. Pat. No. 5,848,365 includes a fuller discussion of these standards.
A variety of techniques have been developed for the extraction, storage and analysis of data from vehicle data links. These techniques have included a variety of communication links including direct connections between the vehicle data links and portable computers having specialized software for downloading the data and displaying the data and storing it for subsequent uploading to desk top and networked computer systems for more detailed analysis and comparison. For the convenience of the system users, a variety of specialized portable computers has been developed to communicate with on-board vehicle electronics. For example, U.S. Pat. No. 5,050,080 to Abe discloses a diagnostic system including a portable diagnostic device adapted to be connected through an adapter harness with an on-board computer based system that is connected with a plurality of actuators for controlling various components of an engine, transmission, suspension system and other vehicular devices. The portable diagnostic device is custom built for the purposes for which it is intended which can add significantly to the cost per unit.
Handheld computers (also known as personal digital assistants) have become quite popular for a variety of functions relating to maintaining personal calendars, personal expenses, calculations, e-mail and other specialized functions. The popularity of these devices has led to high volume sales that has reduced their per unit development costs and allowed further reduction in prices that has fueled further their popularity. These devices are characterized by specialized display screens and memory configurations and often use stylus based operator input systems rather than key pads to reduce size and weight. To operate devices of this type in the most efficient manner and keep electrical power consumption to a minimum, specialized operating systems have been developed for handheld computers. One of the most popular operating systems is known as the PALM(trademark) O/S operating system developed by 3Com. Various aspects of handheld computer systems developed by 3Com are disclosed in U.S. Pat. Nos. 5,727,202; 5,884,323; 5,900,875 and 6,006,274. Another operating system is known as WINDOWS CE(trademark) developed by Microsoft Corporation. While these operating systems are suitable for the purposes intended, the data handling protocols established by these systems do not, without modification, handle other data protocols such as the SAE 1587 protocol. Moreover, the data port of a typical handheld computer (e.g. RS 232) is not compatible with the type of connector normally employed on a SAE 1708 or 1939 data link system.
Accordingly, the ubiquitous nature of handheld devices, their convenience, portability, low cost make them desirable as a device for assisting in the extraction, display and upload of engine/vehicle information for transfer, e.g. via the internet, for analysis but their specialized operating system, limited storage and computing capabilities, limited battery life and their limited porting capabilities make them less than ideal.
Attempts have been made to adapt a handheld computer for the purpose of collecting data. For example, Tescina, Inc. of Fremont, Calif. manufactures a DataGet(trademark) product that allows the collection of gauge values using a Palm(trademark) handheld computer, www.tescina.com. Data is ported from the handheld computer to a personal computer in Microsoft Access(copyright), Microsoft Excel(copyright) or tab delimited text files. Tescina provides a data acquisition module consisting of an analog to digital circuit powered by a battery power source mounted in an adapter housing that attaches directly to the Palm(trademark) handheld computer. However this system in no way suggests how to utilize a handheld computer to connect with a data link (such as a J1708 or J1939) to collect, display and upload in an efficient manner that does not require modification of the operating software that could interfere with the other functions for which the operating software of the handheld device was designed.
The present invention is directed to an vehicle data system for processing and displaying vehicle data transmitted through a bus connector of a data bus on an electronically controlled engine operating in accordance with a predetermined bus protocol, comprising a handheld computer including memory for storing operating system software adapted to operate the handheld computer in accordance with a data protocol which is different from the vehicle bus protocol and an external data port which is physically incompatible with the bus connector of the data bus. The system also includes an adapter for creating a data pathway between the bus connector and the external data port wherein the adapter includes an adapter microprocessor connected via the data pathway with the bus connector for protocol conversion of the data received from the vehicle bus for processing by the handheld computer. The handheld computer may also include a handheld microprocessor for executing the operating system software. The external data port of the handheld computer is connected to the handheld microprocessor to allow the vehicle data when properly formatted to pass into the handheld computer. The adapter may also include a data port connector for connection with the external data port of the handheld computer, a bus compatible connector for connection with the bus connector, and a battery power supply separate from the power supply for the handheld computer and for the data bus. The adapter microprocessor may be supplied with power from the battery power supply.
The adapter may include a flexible cable having a bus compatible connector at one end and a cable connector at the other end, and an adapter housing capable of being affixed to the handheld computer when the data port connector is connected to the external data port. The adapter housing may include a cable compatible connector for engagement with the cable connector to complete the data pathway between the data bus and the adapter microprocessor. The data bus may transfer data messages containing information regarding the vehicle, including engine data and the adapter microprocessor may operate to convert the vehicle data between the bus protocol and the data protocol of the handheld computer. The adapter microprocessor may determine the start and stop of messages received from the data bus. The adapter microprocessor may further operate to add message identifiers to the vehicle data conveyed to the handheld computer through the external data port. The handheld computer may include application software for permitting detection of the message identifiers added to the vehicle data by the adapter microprocessor.
The present invention is also directed to an vehicle data adapter system for creating a data pathway between the bus connector of a data bus on an electronically controlled engine operating in accordance with a predetermined bus protocol to convey data messages and a handheld computer which operates in accordance with a data protocol which is different from the vehicle bus protocol wherein the handheld computer includes an external data port which is physically incompatible with the bus connector of the data bus. The vehicle data adapter system may include an adapter housing external to the handheld computer, an adapter microprocessor included in the data pathway between the data bus and the handheld computer and mounted within the adapter housing, an adapter memory for storing adapter software for implementation by the microprocessor to perform the functions of the adapter system including protocol conversion, a data port connector for connecting the data pathway with the external data port of the handheld computer to allow vehicle data to be transferred to and from the handheld computer, and a bus compatible connector for connecting the data pathway with the bus included in the data pathway for connection with the bus connector of the vehicle bus to allow vehicle data to be transferred to and from the vehicle bus. The adapter microprocessor operates to convert the vehicle data between the bus protocol and the data protocol of the handheld computer by determining the start and stop of the messages received from the data bus. The adapter microprocessor further operates to add message identifiers to the vehicle data conveyed to the handheld computer through the external data port, whereby the amount of processing required by the handheld computer for data monitoring and extraction from the data bus is minimized. The message identifier may include a delimiting header block having a synchronization sequence and a message length. Data link software may also be provided for monitoring selected information for example, regarding engine operating conditions and vehicle information relating to the vehicle in which the engine is mounted. The system may further include application software for causing the handheld computer to function to provide one or more of the following functions: display engine operating conditions, display related vehicle information, display fault information and to allow for change of data and for managing the data storage structure. The system may also include conduit software for transferring data to and from the handheld computer and a personal computer.
The present invention is also directed to a method for creating a data pathway between (1) a data bus on an electronically controlled engine having a first electrical power source which data bus operates in accordance with a predetermined bus protocol to convey multi byte data messages of varying length and (2) a handheld computer having a second electrical power source separate from the first which operates in accordance with a data protocol which buffers received bytes of data for access by application software without keeping track of when the bytes are received thereby losing indications of the start and stop of multi byte data messages, comprising interconnecting the data bus and the handheld computer to form the data pathway external to both the data bus and the handheld computer to allow multi byte data messages of varying length to pass between the handheld computer and the data bus, intercepting the messages conveyed on the data pathway from the data bus to the handheld computer at a point external to the data bus and the handheld computer, buffering the data contained in the intercepted messages external to the data bus and the handheld computer, processing the buffered data to determine the start and stop of messages received from the data bus, adding message identifiers to the buffered data as the messages are conveyed to the handheld computer to identify the start and stop of each message, providing an electrical power source separate from the first and second power sources and performing the intercepting, buffering, processing and adding steps utilizing the electrical power source, whereby the amount of processing that the handheld computer is required to undertake for data monitoring and extraction from the data bus is reduced without employing the electrical power sources of either the handheld computer or the engine.